The industrial used oxy-hydrogen welding machine is to take advantage of mixed gas, which is generated from electrolysis in the electrolytic cell, leading it into a welding gun to reach the function of welding. The theoretic value for the flame temperature of welding gun is at 3640.degree. C. Yet the usage of oxy-hydrate welding gun is not applicable everywhere due to its high flame temperature and low heat. Usually the heat can be heightened and flame temperature can be lowered through altering the fuel molecule composition of a dissolvent made from carbohydrate mixed with hydrogen and oxygen. Nevertheless, only by constantly replacing different oxy-hydrogen dissolvent can this habitual-use installation alternate its flame temperature. Whenever dissolvent being changed, flame with specific temperature can be gained. However, the temperature of the flame is invariable during usage. This makes the installation lack application flexibility and needs replacement of dissolvent all the time or even replacement of the mixing tank, which is relatively inconvenient.
Furthermore, The industrial-used electrolytic cell is generally classified into high voltage and low voltage. The one being used by oxy-hydrogen welding machine belongs to low voltage electrolytic cell. The low voltage industrial-used extraction electrolytic cell for hydrogen and oxygen which most people know about is to use single-pole electrode plate. It is necessary for the high voltage to be lowered through transformer, then commutated and eventually input into electrolytic cell as electrolysis power. Since magnetic loss is one of transformer's trait which results in low power application effectiveness. Moreover, big dimension and heavy weight of transformer also makes the whole machine become hefty and unmovable, which is not good for the interest use. Especially most of this sort of equipments are used as processing machine which lays keen emphasis on its handiness and portability, so lowering down its dimension, weight and enhancing its effectiveness become important goals of research and development. Furthermore, the process through transformer to lower voltage then commute into electrolytic cell, the commutator must be a material with high tolerance of current which causes high heat loss, low effectiveness and prone to burning out. Eventually, in order to generate a large volume of oxygen, it becomes necessary to use a huge electrolysis area of electrode plate to obtain big current electrolysis, so the dimension and weight are needed to be enlarged. All these reasons lead to the heaviness and hugeness on equipment which is of low effectiveness, not good for the operator.